OBJECTIVES: It was the aim of this clinical study to evaluate the long-term outcome of 3- to 4-unit posterior all-ceramic fixed dental prostheses (FDPs) made from veneered zirconia ceramic.

METHODS: Between June 2003 and February 2005, 48 patients received 58 restorations. Twenty-four FDPs had a fixed-to-fixed design (FF) and thirty-four FDPs had a cantilever design (CA). Frameworks were scanned and milled out of 3 mol% yttrium-oxide partially-stabilized zirconia ceramic (CerconBase30, Degudent) and were veneered with feldspathic ceramic (CerconCeramS, Degudent). All FDPs were cemented with glass-ionomer cement (Ketac-Cem, 3 MEspe) after air-abrading the inner crown surfaces.

RESULTS: The mean observation period was 85.4 ± 54 (FF) and 91.7 ± 50 (CA) months, respectively. Ten cantilever FDPs and 5 fixed FDPs were lost due to biological problems of the abutment teeth. Two cantilever FDPs and 4 fixed-to-fixed FDPs were lost due to technical failures of the ceramic materials. The cumulative 13-year survival rate was 43.2% (FF) (CI: 22.8-66.2%) and 52.5% (CA) (CI: 32.5-71.8), respectively. In 13 cases, intraoral repair or polishing of the fractured feldspathic ceramic veneers was needed (7 in group FF, 6 in CA). Eight abutments of six restorations (4 in FF, 4 in CA) had to be treated endodontically and caries therapy was needed in 6 abutment teeth (4 in group FF, 2 in CA). The cumulative 13-year success rate was 29.5% (FF) (CI: 12.1-55.9%) and 22.5% (CA) (CI: 7.9-49.3%).

CONCLUSIONS: Within the limitations of the present investigation, posterior fixed dental prostheses made from veneered zirconia with either a fixed-to fixed or a cantilever design show comparable survival and success rates after 13 years of clinical observation.

CLINICAL SIGNIFICANCE: FDPs made from veneered zirconia ceramic present high failure and complication rates, irrespective of the design (fixed-to-fixed or cantilevered).